The Results of Percutaneous Release of Trigger Digits by Using Full Handle Knife 15º: An Anatomical Hand Surface Landmark and Clinical Study†
Yolchai Jongjirasiri MD*
Affiliation : † This paper was presented at The 6th Congress of the Asian Pacific Federation of Societies for Surgery of the Hand. On 18 November 2006 Shangri-La Hotel. Bangkok, Thailand * Department of Orthopedic Surgery, Bangkok Metropolitan Administration General Hospital
Objective : Know the results of percutaneous release of trigger digits by using full handle knife 15º.
Materials and Methods : The author identified 510 cadaveric digits to find the anatomical landmark of A1
pulley that relates to the knuckle and measurements of A1 pulley lengths. The proximal margin of the A1
pulleys on the perpendicular line from the knuckle to the palm was in the same line in 327 (64.1% ) digits,
while 464 (91.0%) digits were < 1 mm and 509 ( 99.8%) were <2 mm. The average lengths of A1 pulleys in
each digit were as follows: thumb; 5.30, index finger; 6.32, middle finger; 6.58, ring finger; 6.32, and little
finger 5.30 mm. The average lengths of all fingers were 6.13 mm. A further 338 digits of trigger digit in 248
patients were treated by percutaneous release by using full handle knife 15º with these landmarks.
Results : Three hundred and thirty-eight trigger digits were treated. There was a complete resolution of
symptoms in 314 digits (92.90%) when followed up 6 weeks after operation. One digit, an index finger had
residual grade 1 after 3 weeks and complete resolution in 8 weeks. Three digits (0.89%), which were one
thumb and two index fingers, underwent local steroid injection because of painful scar. Nineteen digits
(5.62%) were stiff at proximal interphalangeal joint because of grade 4 triggering and osteoarthritis of the
proximal interphalangeal joint but they increased the range of motion after 6 months. A case (0.30%) had
numbness of the radial tip of the thumb, which may have been caused by injury to the radial digital nerve of the
thumb. No one had open release of A1 pulley.
Conclusion : This technique was a safe and effective out patient procedure on 248 patients and had a complete
resolution of symptoms 92.90%
Keywords : Trigger finger, Percutaneous release, Landmark, A1 pulley, Result
